New Method for Increase of Noise Immunity of GPS Navigation Systems

Abdulov R.N., Asadov H.H.

The paper is devoted to the developed new method for decrease of effect of specially formed jamming signals on functioning of GPS navigation system. The effect of hindering signal of jamming type transmitted by technical means of adversary side is considered. Generation of jamming signal of relevant frequency and sufficient power by adversary is carried out by the aim to reach the condition of non-possibility of receipt of GPS  signals.  The suggested method is based on basic equation of antenna theory, that is Frees equation. According to Frees equation the power of signal receipt by antenna of moving object with defined gain coefficient  can be calculated upon transmission of signal from target objects antenna with known gain coefficient. The new parameter calculated by integration of Frees formula  on passed distance supposing static character of jamming signal source position is suggested. On the basis of research of suggested  parameter the target functional is formed taking into account the motionless position of jamming signal  generator and non-changeable motion direction of moving object toward target containing jamming signal generator. The possible strategies for changing the jamming signal power on transition of object on  route are also taken into account. It is shown that suggested parameter  is of extremum feature upon proportianal or non proportional variation of gain coefficients of antennas of object and jamming signal generator: upon proportional variation the   suggested parameter reaches the minimum and upon inverse identity maximum.  Taking into account the extremum feature of suggested parameter the method and algorithm for decrease of effect of jamming signal on functioning of GPS  navigation systems of similar technical constructions are developed.

https://doi.org/10.31871/IJNTR.5.7.12